Polyalkylene oxide polymerization process and product



N. CALDERCN Jan. 14, 1969 POLYALKYLENE OXIDE POLYMERIZATIQN PROCESS ANDPRODUCT Sheet Filed Aug. 26, 1964 v zllliilri 2 FIG.|

MOLE FRACTION HYDRAZINE IN SECONDARY FIG. 2

COMPON E NT OF CATA LYST MOLE FRACTION HYDRAZINE m SECONDARY INVENTOR-COMPONENT OF CATALYST NISSIM CALDERON United States Patent OfficePatented Jan. 14, 1969 12 Claims ABSTRACT OF THE DISCLOSURE A catalystsystem for vicinal alkylene oxides and vicinal alkylene sulfidespolymerization, comprised of dialkylzinc and hydrazine, results insemicrystalline elastomeric polymers. The poly( propylene oxide)obtained by the described catalyst exhibits solubility and swellingcharacteristics in acetone, which indicate a broad distribution of thecrystalline sequences among the polymer chains. The activity of thedialkylzinc-hydrazine catalyst depends on the molar ratio of hydrazineto dialkylzinc. Best results are achieved when the hydrazine/dialkylzincratio is in the range 0.6-0.8. By using hydrazine/ water combinations asthe secondary component with dialkylzinc, it is possible to preparepoly(propylene oxides) with varying acetone solubility and swellingcharacteristics.

This invention relates to polymerizing epoxides and episulfides. Moreparticularly it relates to a novel catalyst system for polymerizingthese monomers, to the process employing the catalyst, and to theresulting novel polymers. Even more particularly, the invention hasspecial application to that class of epoxides and episulfides known asalkylene oxides and alkylene sulfides, and to multicomponent catalystsystems which employ as a primary component an organo-metallic compound.

A variety of catalysts are known to be capable of polymerizing alkyleneoxides. Such known catalysts are metal halides, metal halide-alkyleneoxide complexes, metal alkoxides, and amides of the alkaline earthmetals. More recently it has been disclosed that metal alkyl compoundsin combination with water or oxygen are suitable catalysts forpolymerizing alkylene oxides (see Polymerization of Alkylene Oxides,Bulletin of Japanese Petroleum Institute, vol. 3, March 1961, JunjiFurakawa et al.). In the particular case of propylene oxidepolymerization, it has been shown that the metal alkyl-water combinationyields a high molecular weight polymer.

High molecular weight polymer chains may possess a molecular structureleading to either a substantially:

crystalline or substantially amorphous (non-crystalline) state ofmatter. Conversely a polymer chain may be composed of alternate blocksof crystallizable and noncrystallizable segments. Crystalline alkyleneoxide polymers, e.g., poly(propylene oxide), are known to be partiallyinsoluble in acetone at 25 0, whereas, amorphous polymers are known tobe soluble in acetone. Consequently,

when individual segments of a substantially crystalline andsubstantially amorphous polymer exist as a physical blend, thecrystalline material may be separated from the amorphous portion bydissolving the latter in acetone. However, if the crystalline andamorphous sequences are in the form of stereoblocks, the polymer willdisplay a lower degree of solubility in acetone thancrystallineamorphous polymer admixtures. The stereoblock polymers willalso exhibit a high degree of swelling in acetone. Gel network formationtheory suggests that the soluble portion will consist of whollyamorphous polymer chains and also those polymer chains having on theaverage less than one sequence of crystalline units per weight averagemolecular weight molecule. Therefore, the degree of solubility of astereoblock polymer depends on the distribution of crystalline sequencesamongst the chains as well as the molecular weight distribution of thepolymer.

The poly(propylene oxide) produced by the process of the inventionutilizing a metal alkyl-hydrazine catalyst system as hereinafterdefined, contains approximately acetone insoluble material. This latterpolymer displays a high degree of swelling in acetone, which is inmarked contrast to the low degree of swelling normally associated withhighly crystalline, highly insoluble polymers. It appears, therefore,that this high swelling, acetone insoluble polymer consists of astereoblock polymer of alternate crystalline and non-crystallinesequences. In addition, the acetone insoluble fractions of the polymersproduced in accordance with this invention have low densities. Thisindicates a low degree of crystallinity which is highly desirable forelastomeric applications. Since the tensile strength and other ultimatestrength properties of elastomers are related to the ability of theelastomer to crystallize on stretching, it follows that the stereoblockpolymers of this invention will be superior to the blend of tactic andatactic polymers often formed by polymerization. This is so because mostof the stereoblock polymer molecules will be able to contribute to theultimate strength, whereas, only the tactic polymers may contributegreatly, to the ultimate strength in the case of polymers consistingessentially of a blend of tactic and atactic chains. The amount oftactic polymer in these blends of tactic and atactic polymers made withother catalysts must necessarily be relatively small in order for thepolymer to remain soft and flexible, hence, one is forced to compromiseultimate strength for flexibility. This compromise is unnecessary withthe elastomers made by this invention as the resulting stereoblockpolymer, by their very nature, are both very flexible and strong.

Because the term stereoblock is not precisely defined or convenient tomeasure quantitatively, and also because it is possible to have varioustypes and relative degrees of stereoblock character in a polymer, anoperational definition for the novel polymers of this invention which isboth unambiguous and also convenient to measure has been selected. Thisdefinition is based on three parameters: (a) the inherent viscosity as ameasure for the molecular weight, (b) the solubility of the bulk polymerin a selective solvent which dissolves the amorphous polymer but doesnot dissolve the crystalline polymer, and (c) the swelling value of theinsoluble portion in the said selective solvent.

The novel polymers of this invention are comprised of epoxides andepisulfides; are substantially gel-free as indicated by their solubilityin a good solvent, i.e. a solvent which will dissolve both amorphous andcrystalline forms of the polymer; are partly crystalline polymers which,after aging for at least 48 hours at a temperature of 30 C. to 60 C.below their melting point, have a swelling value of at least 8, asdetermined in a selective solvent, at a temperature in the range of 30C. to 60 C. below the melting point of the polymer; and their inherentviscosities {1;} are smaller than [ll-.0025 I) where I is the percentinsoluble in the selective solvent. The novel polymers of this inventionare even more preferred 'when their inherent viscosities {1;} aresmaller than [90.01 (SO-D where I has the meaning indicated above.

A good solvent should preferably be a hydrocarbon with a solubilityparameter within ;L1.7 (cal./cc.) units of the solubility parameter ofthe polymer. A definition of the solubility parameter, which is thesquare root of the cohesive energy density, and also a method ofcalculating it, are given in an article by P. A. Small, Journal of Ap- 3plied Chemistry, 3, 71 (1953). Smalls method leads to a value of 7.88(cal./cc.) for the solubility parameter of poly(propylene oxide), hencehydrocarbon solvents having solubility parameters between 6.18 and 9.58(cal./ cc.)" are preferred. Benzene with a solubility parameter of 9.15(cal./cc.) is most preferred.

The critical part of the definition of the polymer of this invention isthe term selective solvent. The important characteristic of a selectivesolvent is that it be capable of dissolving the completely amorphouspolymer, incapable of dissolving the completely crystalline polymer, andcapable of partially dissolving partly crystalline polymers. While thesecharacteristics may be easily ascertained by experimentation obvious tothose skilled in these arts, it may be expected that suitable selectivesolvents will be found in the class of liquids having solubilityparameters which differ by 1.7 to 4.0 (cal/cc) units from that of thepolymer. The preferred selective solvents are ketones whose solubilityparameters are greater than those of the polymer by 1.7 to 3.0(cal./cc.) units. For poly(propylene oxide) the preferred ketones willhave solubility parameters of between 9.58 and 10.88 (cal./ cc.) Acetonewith a solubility parameter of 10.0 (cal./ cc.) is most preferred as aselective solvent. The details of the techniques to measure the amountof polymer insoluble in the selective solvent and the swelling value ofthe insoluble fraction in the selective solvent are given infra.

For poly(propylene oxide), which has a melting point of about 70 C., thepreferred temperatures defined above will be between and 40 C., with themost preferred temperature being 25 C., i.e. in the vicinity of roomtemperature.

The above definition will distinguish the novel polymers of thisinvention, which are characterized by high insolubility and highswelling in the selective solvent, in the practical range of inherentviscosities, i.e. up to values of 11, from all polyepoxide andpolyepisulfide polymers prepared heretofore. The highly crystallinepoly(propylene oxide) prepared with a ferric chloride/ propylene oxidecomplex catalyst has too low a swelling value in acetone (Table II). Thehighly amorphous poly- (propylene oxide) prepared with a calcium amidesystem as catalyst is completely soluble in acetone. Polymers andcopolymers of a relatively random distribution of tactic and atacticstructural units are either less than 24.6% insoluble in the selectivesolvent or have a swelling value of 8.0 or less in the selectivesolvent. A poly(propylene oxide) with stereo block structurecharacterized by many short tactic sequences has a swelling value of 8.0or less in acetone. Mixtures of tactic and atactic poly(propylene oxide)have too high a solubility and too low a swelling value in acetone.

The practical importance of this distribution of crystalline content ina polymer is the retention of good elastomeric qualities which have beenfound to be superior to any rubbery poly(propylene oxide) known.

In its broad scope the subject invention is useful for polymerizingmonomers broadly characterized as epoxide and episulfides, andparticularly those materials known as oxirane and the substitutedderivatives thereof, to form high molecular Weight polymers.Representative examples of substituent radicals of oxirane and thiiranewhich may be usefully employed in the practice of this invention arealkyl, cycloalkyl, aryl, aralkyl, alkenyl, alkoxy and alkenoxy. Alkylradicals containing up to ten carbon atoms are especially preferred.

Representative examples of derivatives of the oxirane epoxides are:ethylene oxide, propylene oxide, l-butene oxide, l-hexene oxide,l-octcne oxide, l-dodecene oxide, l-allyl ethylene oxide, allyl glycidylether, cyclohexyl ethylene oxide, styrene oxide, benzyl ethylene oxide,phenyl glycidyl ether, epichlorohydrin, epibromohydrin, epifiuorohydrin,l-trifiuoromethyl ethylene oxide, glycidyl methacrylate, isobutyleneoxide, 2-butene oxide (cis or trans), 2-octene oxide, cyclohexene oxide,vinyl cyclohexene monoxide or dioxide, 1,1,2-trimethyl ethylene oxide,l,1,2,2-tetramethyl ethylene oxide, cyclopentene oxide,2,4,4-trimethyl-l,2-epoxypentane, 2,4,4-trimethyl-2,3- epoxypentane,1-phenyl-1,2-epoxypropane, toluyl glycidyl ether, chlorophenyl glycidylether, naphthyl glycidyl ether, dicyclopentadiene monoxide or dioxide,isoprene monoxide, limonene monoxide, cyclooctadiene monoxide, butadienemonoxide or dioxide, 4,5-epoxy-hexene-l, 1,4- hexadiene monoxide.

Representative examples of substituted thiirane monomers suitable foruse in practicing this invention are: ethylene sulfide, propylenesulfide, l-butene sulfide, 2- butene sulfide, styrene sulfide,isobutylene sulfide, 1,1,2- trirnethyl ethylene sulfide,1,1,2,2-tetramethyl ethylene sulfide, l-chloromethyl ethylene sulfide.

The catalyst employed in the practice of this invention is a mixture ofat least two components. The primary component is an organo-metallicconstituent with the general formula MR" wherein M represents a divalentmetal. It is preferred to employ zinc, magnesium or cadmium and of thesezinc is most preferred. Each R" represents at least one member selectedfrom the group of radicals consisting of alkyl, cycloalkyl, alkenyl,aryl, aralkyl, alkoxy and hydrogen, and may be the same or dissimilar.The preferred R" substituents are alkyl or aryl radicals, especiallyalkyl radicals containing up to ten carbon atoms.

Representative examples of the primary catalyst component which may beusefully employed in the practice of this invention are dimethyl zinc,diethyl zinc, dibutyl zinc, diisobutyl zinc, diphenyl zinc, dibenzylzinc, diallyl zinc, methyl ethyl zinc, diethyl magnesium, diphenylmagnesium and diethyl cadmium. Diethyl zinc is a convenient and mostpreferred primary component.

The secondary catalyst component employed in this invention is hydrazineor its monoor symmetrically disubstituted derivatives. These may berepresented by the general formula:

wherein each R represents at least one member selected from the groupconsisting of alkyl, aryl, aralkyl, alkoxyalkyl, alkoxy, and hydrogen.

Representative examples of the secondary component which may be usefullyemployed in practicing this invention are hydrazine, methyl hydrazine,ethyl hydrazine, N,N'-dimethyl hydrazine, phenyl hydrazine,N,N'-diphenyl hydrazine, benzyl hydrazine, and N-phenyl-N-ethylhydrazine. Hydrazine is a preferred secondary component.

In practicing this invention the best results for achieving thedesirable stereoblock polymer, consisting of crystalline andnon-crystalline sequences, will be obtained if the secondary componentis employed under conditions which are as anhydrous as practicable.However, there may be occasions where, for a particular application ofthe resulting elastomer, one may wish to make the polymer more or lesscrystalline or amorphous. It has been found that, by including acontrolled amount of water with the hydrazine, it is possible toregulate the degree of stereoregularity introduced into the polymerchain as indicated by the acetone solubility and swelling value of theresulting polymer. In practicing the invention, one may control theresultant stereoregularity of the polymer to any desired point betweenthat achieved by using the known metal alkyl and water (or oxygen, oralcohol) catalyst, and the novel metal alkyl and hydrazine catalyst ofthis invention.

While the amount of catalyst used in the practice of this invention isnot critical, it is to be understood that a sufficient amount should beused to provide a catalytic effect. It has been found that excellentresults are obtained by employing from to one mol of metal alkyl in thecatalyst per liter of monomer and that particularly good results areachieved by using from 10- to 10* mols of metal alkyl in the catalystper liter of monomer.

The ratio of the secondary to the primary catalyst component may varyover a wide range and still enable the catalyst to function. However, ithas been found that there is a limited range wherein substantialconversions result. This range may vary somewhat as the primary andsecondary components vary in their particular formulation. For anyspecific pair of components, however, the optimum molar ratio ofsecondary to primary components may be readily ascertained by techniqueswell known to those skilled in the art and exemplified infra. Thesatisfactory molar ratios of secondary to primary component is usuallyfound in the range 0.1 to 10. The optimum molar ratio is often found inthe range 0.2 to 5. A preferred range for this molar ratio is 0.4 to1.2. In the instant case where the preferred catalyst components,hydrazine and diethyl zinc, are employed with poly(propylene oxide)maximum conversions have been found to occur in the range wherein themolar ratio of hydrazine to diethyl zinc is 0.6 to 0.8.

In practicing this invention the reaction temperature may be varied overa wide range; for instance, from about 50 to about 200 C. It has beenfound that a temperature of from about to about 80 C. is convenient forcarrying out these polymerizations. As is Well understood with reactionsof this type, the reaction time generally increases with decreasingtemperature, although other commonly understood factors also influencethe polymerization rate.

While the process may be conducted at supra-atmospheric, as well assub-atmospheric pressures, such as are frequently utilized forpolymerization reactions, it is an advantage of the subject inventionthat the process may be performed with good results either very near toor at at atmospheric pressure.

The polymerization should be conducted in an inert ambient. Suitable forthis purpose would be an atmosphere of any known inert gas, such asnitrogen, argon, helium; or a vacuum. The polymerization process of thisinvention may be carried out in bulk or in an inert solvent orsuspending medium. Any common aromatic, cycloaliphatic or aliphatichydrocarbon or ether may be used for a solvent; as for example, benzene,cyclohexane, heptane, hexane, diethyl ether, tetrahydrofuran and thelike. Benzene has been found to be generally suitable for this purpose.The inert diluent may be present in the amount of between 0 and 50volumes per volume of episulfides and epoxides used.

In addition to the polymers formed by homopolymerizing monomers of thegeneral type disclosed, the catalyst system of the subject invention maybe used to form saturated copolymers thereof as well as unsaturated,vulcanizable copolymers. Representative examples of the saturatedcopolymers are: copolymers of ethylene oxide and propylene oxide; orcopolymers of ethylene sulfide and propylene sulfide. A conventionallyvulcanizable copolymer would result, for example, from polymerizingallyl glycidyl ether and propylene oxide monomers; or vinyl cyclohexenemonoxide and l-butene oxide monomers; or cyclooctadiene monoxide andpropylene oxide monomers; or bycyclopentadiene monoxide and propyleneoxide monomers. An example of a halo-substituted copolymer is thatformed by copolymerization of epichlorohydrin and propylene oxide. Morecomplicated interpolymers are also envisioned as falling under the scopeof this invention. For instance, to control crystallinity, to improvevulcanizability or otherwise modify and improve the polymers made bythis process, it may be beneficial to use one or more saturated epoxidemonomers in conjunction with one or more unsaturated epoxide monomers;e.g., the product obtained by copolymerizing ethylene oxide, propyleneoxide and allyl glycidyl ether monomers; or propylene oxide, styreneoxide and allyl glycidyl ether monomers; or propylene oxide, allylglycidyl ether and vinyl cyclohexene monoxide monomers.

The rubbery polyepoxides and polyepisulfides produced in the practice ofthe subject invention are high molecular weight polymers (with inherentviscosities exceeding about 0.4 dl./g.), possessing good elastomericproperties when vulcanized. These elastomers may be compounded andprocessed by normal procedures known in the art. They are readilycompounded with fillers such as carbon black and with antioxidants andother conventional compounding materials. The unsaturated elastomers arereadily vulcanized with the aid of conventional sulfur vulcanizingsystems appropriate for the degree and type of unsaturation in theelastomer.

EXAMPLES The practice of this invention is illustrated by reference tothe following examples which are intended to be representative ratherthan restrictive of the scope of this invention. All polymerizationoperations were conducted under a nitrogen atmosphere.

As employed in the data presented infra: inherent viscosity {1 isdefined as the natural logarithm of the relative viscosity at 30 C.divided by polymer concentration (in g./dl.) for a 0.05 to 0.10%solution of polymer in benzene containing 0.1%phenyl-beta-naphthylamine, and is expressed in units of deciliters pergram (dL/g). The swelling value of the acetone insoluble material isdefined as the ratio of the weight of the swollen sample, afterimmersion in acetone for 48 hours at 25 C., to its weight after dryingto constant weight. The swelling value is normally determined on theacetone insoluble fraction of the polymer which has been prepared byextracting out the soluble fraction with acetone, drying the insolubleresidue, molding it at C. into a A thick sheet and storing in the darkat room temperature for 48 hours prior to immersion in acetone todetermine the swelling value. While this rigidly controlled thermalhistory is to be preferred, it is frequently observed that the samevalue is obtained for the swelling value determined on the originalpolymer sample without the prior extraction and molding treatment. Anyvariation from the preferred procedure for determining swelling valuewill be pointed out in the examples infra.

Example 1 A mixture consisting of 2 volumes benzene and 1 volumeproplyene oxide was passed through a silica gel column under nitrogengas. Ninety ml. of this mixture was then charged into a four-ounce glassbottle. 0.135 ml. of anhydrous hydrazine (4.40 10- mols) was then addedto the bottle utilizing common syringe techniques. The bottle was cappedand shaken 15 seconds. Four ml. of a 1.55 molar solution of diethyl zincin heptane was injected into the bottle which was then screw capped. Acontrol bottle from which hydrazine was excluded was prepared similarly.The polymerization bottles were tumbled in a 50 C. water bath for 24hours. The polymerizations were terminated by adding 10 ml. of methanolcontaining 0.2 gram of phenyl-beta-naphthylamine into each of thepolymerization bottles. The contents of the bottle were then boiled inwater for 2 hours to destroy the excess catalyst and precipitate thepolymer. The product was subsequently dried in a vacuum desiccator.

A series of polymerization runs were conducted by varying the amount ofanhydrous hydrazine in the above recipe, thus changing the molar ratioof hydrazine to diethyl zinc in the catalyst.

Table I presents the results of these experimental runs.

1 Trace amounts. 1 Insufficient polymer to determine [1,].

Example 2 A sample of poly(propylene oxide) was prepared according tothe procedure of Example 1. A second sample of poly(propylene oxide) wasprepared by a similar procedure except that water was substituted forhydrazine as cocatalyst. The molar ratio of diethyl zinc to water was1:1. In addition, a sample of highly tactic poly(propylene oxide)prepared with a catalyst comprising an iron salt was added to theseries. These samples were extracted with acetone for 72 hours at roomtemperature. The percentage of acetone insoluble polymer for each samplewas determined and is given by 100 Wa/Wo, where W is the weight ofpolymer before extraction and Wu is the weight of polymer recoveredafter the acetone extraction and drying in a vacuum oven for 24 hours atroom temperature and torr.

The acetone insoluble portions were molded at 85 C. into A" sheets andstored in the dark at room temperature for 48 hours. The swelling valuein acetone was determined for these three acetone insoluble sampleshaving the same thermal history. In addition, the densities of theseacetone insoluble samples were determined using a density gradientcolumn. The data are disclosed in Table II.

A series of polymerizations similar to that conducted in Example 1 werecarried out using hydrazobenzene instead of hydrazine. Various molarratios of hydrazobenzene were applied to diethyl zinc. The remainingvariables were maintained as noted in Example 1 with the exception ofpolymerization time. After 90 hours the solid polymers were isolated asin Example 1 and the inherent viscosity, the acetone insolubility andthe swelling value of the acetone insoluble fractions were determined.These are presented in Table III.

TABLE III Sample (C.-.H NH)1/ Percent 1 Percent Swelling N o. R":Z11,conver- (dl.7g.) Acetone value Molar ratio sion insoluble Example 4 Apolymerization run similar to that conducted in Example 1 was carriedout using 10 ml. of methyl thiirane (propylene sulfide) monomer in ml.of benzene. 0.112 ml. of anhydrous hydrazine and 2.4 ml. of diethyl zinc(1.94 molar in benzene) were added. The molar ratio of hydrazine todiethyl zinc was 0.68:1. Polymerization was allowed to proceed in a 30C. water bath. The polymerization bottle was shaken periodically. After16.7 hours, the polymerization mass was precipitated in excess methanolcontaining phenyl-beta-naphthylamine antioxidant. The amount of driedpoly(propylene sulfide) was 3.9 g. (42% yield). The inherent viscositywas 0.42 dl./ g.

Example 5 A five gallon polymerization reactor equipped with amechanical stirrer was dried and flushed thoroughly with nitrogen for 45minutes. A mixture containing 13 liters of benzene, 4 liters ofpropylene oxide and 2 liters of allyl glycidyl ether was introduced tothe reactor followed by the addition of 38 gms. (0.31 mol) of diethylzinc in :heptane solution. After stirring the mixture about 5 minutes,6.3 gms. (0.20 mol) of anhydrous hydrazine was injected into themixture. The reactor temperature was raised to 80 C. and maintained atthis temperature during the copolymerization process. Thecopolymerization was terminated after 18 hours by injecting 5 gms. ofphenyl-beta-naphthylamine dissolved in 40 ml. of methanol. The copolymercement was removed from the reactor, coagulated in boiling water anddried in a vacuum oven. A 63.5% yield was obtained, based on the weightof the monomers charged.

Example 6 The copolymer of propylene oxide (PO) and allyl glycidyl ether(AGE) prepared in Example 5 was com pounded according to the recipe inTable IV.

Table IV Parts PO/AGE Copolymer HAP-Carbon Black 50 Zinc oxide 5 Stearicacid 3 Sulfur 2 Tetramethyl thiuram disulfide l Tellurium diethyldithiocar bamate 0.5

This compound was divided into four portions which were cured at 153 C.for 15, 30, 45 and 60 minutes. Table V discloses the physical test dataobtained from an analysis of these respective cure samples. Stress,strain properties were determined at 25 C. on an Instron TestingMachine. The dumbells had a narrowed cross section of 0.1 x 0.625 inchover a length of 0.9 inch. The crosshead speed was two inches perminute.

as the best cure time for a compound mixed according to the recipe inTable IV. Table VI contains additional physical properties of thevulcanizate of poly(pr0pylene oxide/ allyl glycidyl ether) copolymer asobtained by a 45 153 C. curing rate.

TABLE VI Physical Test Value A.S.'I.M. Test Procedure Rebound Resilience(percent) at- 23 C 58. D1054-55. 100 C 66. 7 D1054-55. Shore A Hardness74 D676-55T.

525 D624-54, Die C. 285 D024-54, Die C.

While all these physical properties are excellent, the crescent tearstrength values are outstanding, particularly at the highertemperatures. A similar copolyrner made with a diethyl zinc/watercatalyst system, and vulcanized similarly, had a crescent tear strengthof only 218 pounds per inch of 100 C. This difference is representativeof the marked superiority of the stereoblock polymers and copolymers ofthis invention over the polymers and copolymers made heretofore and isalso indicative of the superiority of the novel catalyst system usedhere over those used previously.

Example 7 It was observed that the increase in conversion of thepolymerizing systems was faster in the case of those recipes containingincreasing amounts of water as the secondary component of the catalyst.The diethyl zinc/water catalyst gives faster polymerization than thediethyl zinc/hydrazine catalyst system. The results on these experimentsare tabulated in Table IX. The procedure followed for the determinationof percent insoluble in acetone was identical for all the polymersamples. An accurately weighed sample (1 gram) was placed in a bottlecontaining 200 ml. of acetone and kept in the dark for 65 hours at roomtemperature. After centrifuging for 15 minutes, 10 ml. aliquots weretaken from the clear solution and placed in pre-weighed aluminum cups.These were evaporated to constant weight to allow determination of theamount of polymer soluble in acetone and thus allowing the calculationof the percent insoluble in acetone by difference. The swelling value ofthe acetone insoluble fraction was determined by the preferred procedurewith the trivial exception that 72 hours immersion in acetone was usedrather than 48 hours.

TABLE IX Mol Fraction Percent Swelling Run No. of NgH4 (1 Acetone ValueInsoluble 0. 000 4. s2 22. s 6. 85 0. 081 6. 36 55. 5 8. 0. 123 7. 2050. 1 8. 40 0. 158 8. 38 59. 5 14. 00 0.202 5. 10 53. 9 7. 79 0. 3656.40 60. 1 12. 29 0. 432 9. so 71. 2 15. 0a 1. 000 14. 20 7s. 4 20. 55

Note that as little as 0.1 mol fraction of hydrazine in the secondarycatalyst component has markedlv increased TABLE VII Combined PercentSample Catalyst System Weight vi Acetone Swelling (dl./g.) InsolubleValue 1 (C:H5)zZIl/N;H 8. 80 36. 4 15 8 2 (CzHo)2Zn/N:H4-- 9. 20 16.711.8 3..--

(CIH5)2Zl1/H20 4. 79 10.5 41.10 4 (hHshZn/Hzo- 5. 73 6. 1 52. 50 5----FBC 3/P0 2.14 23.8 7.37 FeCl3/PO 97/6 1.87 17.8 12.55 7 CB-(NHz): System97/3 3. 82 0. 0

Example 8 the amount of acetone insoluble material formed and also Aseries of runs was conducted wherein, to a constant amount of diethylzinc, a varying mixture of H 0 and N H was added. Eight 4-oz. bottles,dried in an oven at 120 C. for 48 hours and flushed with nitrogen, werecharged with 90 ml. of a benzene-propylene oxide (2:1 by volume) mixturewhich had been passed through a silica gel column. Into each of thesebottles four ml. of diethyl zinc solution in heptane (1.55 molar) wasinjected after the H O+N H mixtures had been added. The bottles wereplaced in a 50 C. water bath for 24 hours. Termination Was accomplishedby adding 10 ml. methanol, followed by boiling the contents of thebottle in water for 2 hours followed by drying in a vacuum desiccator,Table VIII includes the polymerization recipe data related to thisseries of runs. The amounts of diethyl zinc, water and hydrazine usedare given in millimols.

TABLE VIII [HzO]+lNiI-I4] Run M01. Frac. No. [(Cz s)2 l 2 l zHil of N1114* z sh u] Molar Raine [N 1H4] 'Mol fraction of N;H

[ z d-i-[ 2 increased its swelling value with little change in theinherent viscosity. All polymers in Table IX prepared with catalystscomprised at least in part of hydrazine are more than 50.1% insoluble inacetone and the swelling value is greater than 7.79.

FIGURES l and 2 are plots of the data listed in Table VIII and show themarked non-linear dependence of both the percent insoluble in acetoneand swelling value on the mol fraction of hydrazine in the secondarycomponent of the catalyst. The marked non-linear dependence of theseproperties on the mol fraction of hydrazine in the secondary componentof the catalyst proves that the diethyl zinc/Water-hydrazine catalyst isa diiferent catalyst from that obtained by the use of either diethylzinc/water or diethyl zinc/hydrazine catalyst systems alone or inphysical admixture. If the diethyl zinc/water-hydrazine catalyst systemwere to act as a simple physical blend of diethyl zinc/ water anddiethyl zinc/ hydrazine catalysts of equal reactivity then the linearbehavior indicated by the dashed lines in FIGURES l and 2 would beexpected. However, the diethyl zinc/hydrazine catalyst is not asreactive as the diethyl zinc/ water catalyst and hence one should expecta behavior of the qualitative appearance shown by the dash-dotted linesin FIGURES 1 and 2; i.e., a curve convex to the abscissa, if the novelcatalyst of this invention were to act as a simple admixture of diethylzinc/ hydrazine and diethyl zinc/ water catalysts. The solid lines ofFIGURES 1 and 2 represent the averaged observed dependence of thepercent insoluble in acetone or swelling value on the mol fraction ofhydrazine in the secondary component of the catalyst. Since thisbehavior; i.e., a curve concave to the abscissa, is opposed to thatexpected for simple admixtures of diethyl zinc/ water and diethylzinc/hydrazine catalysts, we must conclude that the diethylzinc/water-hydrazine catalyst is a totally novel catalyst.

Example 9 FIGURE 3 illustrates a plot of the percent insoluble inacetone vs. the inherent viscosity for poly(propylene oxide) polymerswhich were prepared by diethyl zinc/ water, diethyl zinc/hydrazine-waterand diethyl zinc/ diphenyl hydrazine catalytic systems. All thesepolymers are substantially amorphous having swelling values above 8.However, the polymers made with catalysts Comprising diethylzinc/hydrazine, diethyl zinc/diphenyl hydrazine and diethylzinc/hydrazine and water have a higher percent insoluble figure than thediethyl zinc/H O system for any given inherent viscosity in thepractical range of -110 dl./g. This suggests that although the polymersprepared by diethyl zinc/hydrazine (or its derivatives) and diethylzinc/water have roughly the same amount of crystalline material, thedistribution of the crystalline sequences between the chains in thepolymers prepared by the diethyl zinc/hydrazine (or its derivatives) ismore uniform, yielding an elastomer with good physical properties. Itwas found that the following relationships characterize thepoly(propylene oxides) prepared by diethyl zinc/hydrazine, diethylzinc/hydrazine-water and diethyl zinc/diphenyl hydrazine catalysts anddifferentiate them from poly(propylene oxides) made with all other knowncatalyst systems:

inherent viscosityll.0025 (90-1) swelling value- 8 where I representspercent insoluble in acetone.

While certain representative embodiments and details have been shown forthe purpose of illustrating the invention, it will be apparent to thoseskilled in this art that various changes and modifications may be madetherein without departing from the spirit or scope of the invention.

What is claimed is:

1. The method for polymerizing vicinal alkylene oxides and vicinalalkylene sulfides which comprises:

(1) contacting a monomeric material which comprises at least one memberof the group consisting of vicinal alkylene oxides and vicinal alkylenesulfides with the formula (a) wherein Q is a member of the groupconsisting of oxygen and sulfur;

(b) wherein each R is at least one member of the group consisting ofalkyl, cycloalkyl, aryl, aralkyl, alkenyl, alkoxy, alkenoxy, hydrogenand mixtures thereof, containing up to 10 carbon atoms in each R;

(II) a catalytic amount of a catalyst comprising a mixture of:

(a) at least one component with the formula MRI!2 (1) wherein each R isselected from the group consisting of alkyl, cycloalkyl, alkenyl, aryl,aralkyl, alkoxy, hydrogen and mixture thereof, containing up to 10carbon atoms in each R";

(2) wherein M is a divalent metal selected from the group consisting ofzinc, magnesium, cadmium and mixture thereof; and

(b) at least one component with the formula wherein R represents atleast one member of the group consisting of an alkyl radical containingup to 10 carbon atoms and hydrogen.

3. The process according to claim 1 (A) wherein the monomer isrepresented by the formula (B) wherein R is at least one member of thegroup consisting of alkyl radicals containing up to 10 carbon atoms andhydrogen;

(C) wherein each R comprises at least one member of the group consistingof aryl radicals and alkyl radicals containing up to 10 carbon atoms;and

(D) wherein each R comprises at least one member of the group consistingof aryl radicals, alkyl radicals and containing up to 10 carbon atomsand hydrogen; and

(E) wherein the ratio of RHN-HNR to MR is between 0.4 and 1.2.

4. The process according to claim 3 wherein each R represents an alkylradical containing up to 10 carbon atoms; and each R comprises at leastone member of the group consisting of an aryl radical and hydrogen.

5. The process according to claim 4 wherein R represents a phenylradical.

6. The process according to claim 4 wherein M represents zinc and Rrepresents hydrogen.

7. The process according to claim 1 wherein a monomeric materialcomprises from to 100% propylene oxide and from 20 to 0% allyl glycidylether; wherein MR" represents diethyl Zinc; wherein RHN-NI-IR representshydrazine; and wherein the molar ratio of hydrazine to diethyl zinc isbetween 0.6 and 0.8.

8. The process according to claim 7 wherein the molar ratio of water tohydrazine is zero.

9. A composition of matter comprising the polymerization product of atleast one member selected from the group consisting of vicinal alkyleneoxides and vicinal alkylene sulfides, characterized by:

(A) being gel-free as indicated by its complete solubility in a goodsolvent as hereinbefore defined;

(B) being partly crystalline as indicated by at least 24.6% insolubilityin a selective solvent capable of dissolving the completely amorphouspolymer but incapable of dissolving the highly crystalline polymer at atemperature of 30-60 C. below the melting point of the polymer and afteraging the polymer for at least 48 hours in this temperature range;

(C) possessing an inherent viscosity {7;} (dL/g.) in a hydrocarbonsolvent with a solubility parameter within 1.7 (cal./cc.)" units of thesolubility parameter of said polymerization product, and said inherentviscosity is less than [ll-.0025 (I) where I is the percent insoluble inthe selective solvent; and

(D) having a fraction insoluble in the selective solvent which has aswelling value, as hereinbefore defined, in the selective solvent of atleast 8.

10. A composition of matter according to claim 9 wherein the solvent of(C) is benzene and the selective solvent is acetone.

11. A composition of matter according to claim 9 wherein the polymercomprises the polymerization product of at least one member selectedfrom the group consisting of alkylene oxides and alkylene sulfides withup to 12 carbon atoms per monomer molecule.

12. A composition of matter according to claim 11 wherein the polymer iscomprised of the polymerization product of a mixture of propylene oxideand allyl glycidyl ether.

References Cited FOREIGN PATENTS 5/1964 Great Britain.

OTHER REFERENCES I. of Polymer Science, vol. 47, issue 149 (1960), pp.486-488 relied on.

